This invention relates to habitat for caged animals such as nesting rodents.
Conventionally, caged animals including laboratory animals and rodents such as mice, rats, hamsters and gerbils are kept in an enclosure in the form of a box or glass-walled tank, strewn with litter.
The rodents burrow into the litter to make nest spaces and also separate areas for their excreta. The litter becomes soiled and needs constant replacement. Particularly in a laboratory environment, this is a labour-intensive operation. Where numbers of animals are kept, there is always a risk of cross-infection from enclosure to enclosure if cleaning implements and materials are used incautiously, and animals may react to changes in the comfort quality of litter changes, either because a different material is used or because of differences in the way different attendants introduce new litter to an enclosure.
Thus far the market has been relatively conservative in its demands for animal bedding products, and to a certain extent the products such as wood bedding, hemp, corn etc have been presented in an open format and dispensed with scoops into the animal cages.
There are no set volumes for the amount needed used within the various size cages, so it has to a greater degree been at the discretion of the dispensing worker. Therefore this can lead to overfilling or underfilling which may have adverse effects on the welfare of the animals within a given cage and also has the inherent problem of budget costs (value for money).
The continued developments of isolator technology and individual ventilated cage systems pose their own additional problems, and increased concerns of allergen controls have made the dispensing and removal of cage bedding a much more critical process.
The present invention addresses these problems.
The invention comprises habitat for caged animals, for example nesting rodents, comprising a penetrable envelope containing litter.
The envelope may be penetrable by gnawing or chewing, and may be biodegradable, and edible, or of food grade material. A woven or non-woven fabric of a natural or reconstituted cellulose fibre or depending on application a porous plastic sheet may be used for example.
The liner may also be biodegradable and, desirably, absorbent. It, too, may be of cellulosic material such as, for example, paper, sawdust e.g. dust-free whitewood sawdust, crushed corn cob, hemp, or of pelleted cellulosic material such as is used for cat litter.
The envelope may also contain additional substances or xe2x80x9cenrichment productsxe2x80x9d for example foodstuffs or other ingredients such as medicaments or toys such as cardboard tubes. Thus a habitat may be provided containing foodstuff laced with antibiotics to effect treatment of an unwell animal.
The present invention is particularly suitable for a modern retail environment such as supermarkets, providing sealed unit envelopes containing litter which are suitable for packaging and presentation on shelves and display units.
One embodiment of habitat according to the invention will now be described with reference to the accompanying drawing, in which the single Figure is a part cutaway perspective view.
The habitat comprises a penetrable envelope 11 containing litter 12.
The envelope 11 is of a perforate paper mesh, akin to a large tea bag, though any of a variety of other materials that may be air permeable, biodegradable, chewable, edible or food grade, for example a perforate bread wrapping, may serve.
The litter 12 is for example of white wood sawdust, but could be of shredded or pelleted paper or any other material conventionally used for animal litter. It is preferably absorbent so that soil areas do not become waterlogged.
In use, the litter-filled envelope 11 is simply placed at the bottom of an animal enclosure. Rodents will readily chew through the envelope 11 and burrow into the litter 12 for nesting and soil areas.
Because the habitat is a manufactured item rather than a bulk supply of litter, stricter controls can apply as to depth of litter, packing density and so forth, and various additives can be used for purposes of environmental enhancement.
Cleaning cages, tanks and other enclosures is simplified as the need to sweep or shovel can be greatly reducedxe2x80x94the remains of the filled envelope and its contents merely has to be lifted out, any fauna inhabiting the same coaxed out, and a fresh habitatxe2x80x94which can be essentially guaranteed identical with the old one, dropped into the enclosure, the fauna being then reintroduced to make new nesting and soil areas.
Risk of cross infection may be reduced because cleaning out an enclosure can be simplified as the old habitat can easily be removed and a new one dropped in place depending on local practices.
In the domestic environment, cleaning out becomes less of a chore, hence is less likely to be avoided, while pets are assured of a uniform standard habitat.
The dimensions of the habitat can be chosen to be suitable for any particular rodent, or a universal model can be made that will serve for the larger animals as well as the smaller ones. Probably, a depth of 10 cm will serve for most burrowing rodents (except rabbits, of course and rodents such as coypu which, in captivity, probably don""t burrow in any event) the other dimensions corresponding to those of, say, laboratory standard enclosures or domestic pet enclosures for which the habitat may be specifically designed.
Experiments (below have also been performed to test the acceptability and usefulness of the habitat of the present invention (also referred to as xe2x80x9cNestpaksxe2x80x9d).
Overview
Male and female Wistar Rats and MF1 mice at different ages were placed in various cage systems, including a triple preference unit. They where observes with sawdust alone, sawdust and shredded paper and sealed test packs, in single cages with only one product at a time, and in a preference system, where they were allowed to choose the product to inhabit.
When given no choice (single cages) sawdust alone did not create much activity apart from xe2x80x9chotel syndromexe2x80x9d, whereas when given shredded paper, most animals made some form of nest. When the sealed test packs were presented, a much greater amount of activity was observed, with the animals chewing and burrowing into the packs. In all cases they dispersed the sawdust around the cage and made some form of nest with the paper sacking.
When given a choice (preference system) in which each of the three products were presented in one of the three cages, there was a great deal of activity observed, and in all cases the sealed nest packs caused enough interest to encourage the animals to tear open and dispense the sawdust and utilise the pack as nesting material.
The trails have proved conclusively that the sealed Nestpak can provide the animals with a valuable stimulus to their environment, whilst being extremely labour saving in storage and dispensing into the cages in both open and enclosed caging systems.